Integrating Past, Present, and Future Approaches - Spatial Mathematics: Theory and Practice through Mapping - page 227

10.4.2.2 Online
Start the “real time closest facility” application on: http://nadev.arcgis.com/arcgis/
samples/101/FlexProjects/CF-RT10/bin-release/Main.html. Once the application
loads, click on a point anywhere on the map to start the response of fire and police
vehicles. Note the routes the vehicles take to the incident, the relationship of distance
and major roads to the incident, and the critical role that the ability to map and
monitor real-time vehicle and incident locations makes in emergency response.
To further explore the effect that posted road speed and road width have on the travel
time of speciic vehicles, visit the Fast Service Area application on: http://nadev.
arcgis.com/arcgis/samples/101/JS/FastServiceArea.html. This application shows the
areas within a 5 minute drive time of the point your computer mouse lies on. Pan the
mouse just north of Whittier in the mountains. Then pan the mouse to the northwest
of this point, at the intersection of Highway 60 and I-605, noting the enlarged shape
when the highways are included.
What influence does traffic have on accessibility and response? To find out, access the
“routing with trafic” application on: http://nadev.arcgis.com/arcgis/samples/101/
JS/Route101-traffic.html. Create a route on the map by clicking once for the starting
point (move to a different location) and then by clicking another time for the ending
point. Note how the time to travel that route changes based on traffic on US Highway
101. Increased traffic during peak commuting times definitely raises the time
required to get from Point A to Point B.
At times, barriers from construction, special events such as parades, traffic, or
emergencies can affect routing. To observe the effect of these barriers, visit the route
task example for barriers, on: http://nadev.arcgis.com/arcgis/samples/
RouteTaskEx/Barriers.html . Click on the map of London on Fitzrovia north of the
River Thames to start the route and on Spring Gardens south of the river to end the
route. How does the route take into account the natural barrier of the river? The route
seeks obvious crossing points at bridges.
This map shows the fastest route between the two points. Why is the fastest route
oftentimes not the shortest route? The fastest route could be because of lower traffic,
one-way streets, fewer traffic lights, wider roads, or other factors. Now, set up some
barriers: Draw a few point barriers, line barriers, and polygon barriers on the map
and note how much time and distance they add to the route.
In the next section, you have the opportunity to construct your own routes,
first for a tour bus company at a local scale in Manhattan, and then for a truck-
ing company at a national scale for the USA.